LaMontagne et al., 2011¹⁴

For surveys in India, Peru and Uganda and for the first year in Viet Nam, a two-stage cluster sample design was used. The primary sampling cluster was the census district or census enumeration area within the prespecified geographical boundary of the vaccination programme. The secondary sampling unit was the household within each cluster. Each country’s census department, with the exception of Peru’s, drew the sample using recent data and provided a list of clusters and locations to the research team. In Peru, the research team randomly selected clusters after each available cluster within the geographical boundary of the programme was enumerated and listed. The selection of households started at a central or randomly selected location in the cluster and progressed from house to house using the next-nearest-household approach.

For the second year survey in Viet Nam, systematic random sampling from a complete census of all eligible households was used. The sample was drawn for each of the two vaccination strategies from three geographical areas in which the programme was implemented (i.e. six separate samples). A random number generator determined the starting point and the sampling interval and was applied to each list of households that contained girls eligible for vaccination.

India

Peru

Uganda Vietnam

India (2009) - 3921

Peru (2008) - 575

Uganda (2008) - 761

Uganda (2009) - 728

Vietnam (2008) - 780

Vietnam (2009) - 504

7269

Range: 9 - 14^a

Most of the eligible girls were in grade 5 (23.6%) and grade 6 (26.5%) of school.